Intraprocedural stent thrombosis during implantation of sirolimus-eluting stents.

BACKGROUND Intraprocedural stent thrombosis (IPST) is a rare event (<0.01% in our experience with bare metal stents), with the exception of specific settings such as acute myocardial infarction, thrombus-containing lesions, and dissections. We report the occurrence of this event during elective implantation of sirolimus-eluting stents. METHODS AND RESULTS Between April 2002 and August 2003, 670 patients with 1362 lesions were treated with Cypher (Cordis, Johnson and Johnson Co) sirolimus-eluting stent implantation in San Raffaele Hospital and EMO Centro Cuore Columbus. Diabetes mellitus was present in 142 patients (21%), and 164 (24.5%) had unstable angina. Pretreatment with glycoprotein IIb/IIIa (GP IIb/IIIa) inhibitors was carried out in 235 patients (35%). Total stent length per vessel was 42.9+/-28.3 mm. IPST occurred in 5 patients (0.7%). None of the patients with IPST were pretreated with GP IIb/IIIa inhibitors. Using univariate exact logistic regression, only total stent length per vessel, in millimeters (exact OR, 1.03; 95% CI, 1.011 to 1.046; P=0.0028), was associated with the occurrence of IPST. CONCLUSIONS Stent length was associated with the occurrence of IPST. Particular attention will need to be directed to this potential complication when long sirolimus-eluting stents are being used.